Code breaker

Dive into the detective world with this portable Three Detectives Cryptex! Every sharp-witted detective needs a secret storage vault for guarding important clues and other treasures. So, carefully choose a unique 6-figure numerical combination, program it in, and keep the code hidden somewhere safe!

Cryptex toyLogo for online gift shop, Coolthings Australia, be the coolest gift giver.
To be in the running to win a Cryptex from Coolthings Australia (, break this code and send us a photo of your answer.
DH49 code breaker competition grid
Hint: A = 1–1, B = 1–2, C = 1–3
4–3 4–5 4–3 3–5 2–4 1–3 2–4 3–4 4–5 4–3    1–3 2–3 1–1 4–2 1–1 1–3 4–4 1–5 4–2

How to enter

To be in the running to win one of these fantastic prizes, photograph your entry and email it to by 31 August 2021. Include your name, age, address and Double Helix subscriber number*. Get a parent’s permission, and ask them to sign each entry. The best entries in each competition will win.

*Don't know your subscriber number? Check the address label that came with your magazine or subscribe now.

Terms and conditions of entry

1. To be valid, all entries must include name, address, age of entrant and Double Helix subscriber number. 2. All entries become the property of CSIRO and will not be returned. 3. Entering the competition assigns copyright to CSIRO. 4. Entries will be judged on creative merit, not by chance. 5. Age will be taken into consideration when judging. 6. All decisions on competitions are final and will not be discussed further. 7. Winners will be notified by mail and the names of competition winners only will be published three issues later. 8. CSIRO shall not be liable for any damage or loss suffered in connection with any of the prizes. 9. Any change in value of the prize between the publishing date and the delivery date is not the responsibility of CSIRO. 10. In the case that prizes become unavailable after the publishing date, CSIRO will send an alternative prize. 11. The closing date for this issue's entries is 31 August 2021. 12. Competition entries must be the entrant's own work. 13. It is the responsibility of the entrant to ensure copyright of their entry is not assigned elsewhere. 14. Winners should allow six weeks for prize delivery.


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